On 10/4/25 16:36, Pierrick Bouvier wrote:
On 4/10/25 05:14, Philippe Mathieu-Daudé wrote:
Hi Pierrick,
On 13/12/22 00:05, Philippe Mathieu-Daudé wrote:
The current definition of VHOST_USER_MAX_RAM_SLOTS is
target specific. By converting this definition to a runtime
vhost_user_ram_slots_max() helper declared in a target
specific unit, we can have the rest of vhost-user.c target
independent.
To avoid variable length array or using the heap to store
arrays of vhost_user_ram_slots_max() elements, we simply
declare an array of the biggest VHOST_USER_MAX_RAM_SLOTS,
and each target uses up to vhost_user_ram_slots_max()
elements of it. Ensure arrays are big enough by adding an
assertion in vhost_user_init().
Signed-off-by: Philippe Mathieu-Daudé <phi...@linaro.org>
---
RFC: Should I add VHOST_USER_MAX_RAM_SLOTS to vhost-user.h
or create an internal header for it?
---
hw/virtio/meson.build | 1 +
hw/virtio/vhost-user-target.c | 29 +++++++++++++++++++++++++++++
hw/virtio/vhost-user.c | 26 +++++---------------------
include/hw/virtio/vhost-user.h | 7 +++++++
4 files changed, 42 insertions(+), 21 deletions(-)
create mode 100644 hw/virtio/vhost-user-target.c
diff --git a/hw/virtio/meson.build b/hw/virtio/meson.build
index eb7ee8ea92..bf7e35fa8a 100644
--- a/hw/virtio/meson.build
+++ b/hw/virtio/meson.build
@@ -11,6 +11,7 @@ if have_vhost
specific_virtio_ss.add(files('vhost.c', 'vhost-backend.c',
'vhost-iova-tree.c'))
if have_vhost_user
specific_virtio_ss.add(files('vhost-user.c'))
+ specific_virtio_ss.add(files('vhost-user-target.c'))
endif
if have_vhost_vdpa
specific_virtio_ss.add(files('vhost-vdpa.c', 'vhost-shadow-
virtqueue.c'))
diff --git a/hw/virtio/vhost-user-target.c b/hw/virtio/vhost-user-
target.c
new file mode 100644
index 0000000000..6a0d0f53d0
--- /dev/null
+++ b/hw/virtio/vhost-user-target.c
@@ -0,0 +1,29 @@
+/*
+ * vhost-user target-specific helpers
+ *
+ * Copyright (c) 2013 Virtual Open Systems Sarl.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "hw/virtio/vhost-user.h"
+
+#if defined(TARGET_X86) || defined(TARGET_X86_64) || \
+ defined(TARGET_ARM) || defined(TARGET_ARM_64)
+#include "hw/acpi/acpi.h"
+#elif defined(TARGET_PPC) || defined(TARGET_PPC64)
+#include "hw/ppc/spapr.h"
+#endif
+
+unsigned int vhost_user_ram_slots_max(void)
+{
+#if defined(TARGET_X86) || defined(TARGET_X86_64) || \
+ defined(TARGET_ARM) || defined(TARGET_ARM_64)
+ return ACPI_MAX_RAM_SLOTS;
+#elif defined(TARGET_PPC) || defined(TARGET_PPC64)
+ return SPAPR_MAX_RAM_SLOTS;
+#else
+ return 512;
Should vhost_user_ram_slots_max be another TargetInfo field?
I don't think so, it would be better to transform the existing function
in something like:
switch (target_current()) {
case TARGET_X86:
case TARGET_ARM:
case TARGET_X86_64:
case TARGET_ARM_64:
return ACPI_MAX_RAM_SLOTS;
case TARGET PPC:
case TARGET PPC64:
return SPAPR_MAX_RAM_SLOTS;
default:
return 512;
}
Clever, I like it, thanks!
